This common knowledge enough that this does not need a citation. Its not just the addiction part, votes get caste on whether the candidate will hand out some free alcohol, a color TV and some cash as a one time incentive to get their vote. The thing is that this works in many states of India. Since getting the votes is so easy (although there is some arms race among the candidates) it should not be a surprise that after being elected these candidates are after their own interest (wealth grab) than do their job of representing the people.
The problem is much more deep-rooted than addiction. There is a large class of people who have not benefitted from the democracy in the ~60 odd years of independence. The way they think is, "I am not going to get anything out of this anyway, neither did my earlier generation. This way I will at least get a TV and some free booze"